Tag Archives: Omega-3

Top 10 Paleo Foods for Heart Health | The Paleo Diet

One of the things I love most about a True Paleo regime is being able to enjoy so many of the foods I used to think were unhealthy choices.

And despite diet trends coming and going, many people get caught up with some of the less healthy versions along with the inaccurate hype that tends to surround them.

Some of the foods I now savor are ones I never would have dreamed of eating a mere decade ago, simply because I thought they were too high in fat (90’s mindset), didn’t provide enough carbohydrate (Endurance athlete? Go heavy on the carbs.), or simply because the sheer number of calories might exceed what I’d need in a given day (Exercise physiology thesis: Calories In vs. Out is the single, most important factor in determining whether you would lose weight, gain weight or stay the same), source of calories aside.

Testing and trying a number of ways of eating thankfully brought me back to a Paleo diet in 2005. Guess what? The many foods I didn’t consider are ones I’ve come to relish. It turns out they not only taste great, but are increasingly beneficial to our health.

February is National Heart Month and there is no better diet than a Paleo diet to promote heart health.

Salmon

One of the best sources of anti-inflammatory omega-3 fatty acids which can lower the risk of irregular heart beat as well as plaque build up in the arteries. 1  Stick with wild, not farmed.

Blueberries

Rich in anthocyanins and flavonoids, antioxidants that can decrease blood pressure and dilate blood vessels.2 Freezing wild berries makes for a surprisingly decadent treat, all on their own!

Citrus

High in flavonoids that are linked with a reduced rate of ischemic stroke caused by blood clots, and rich in vitamin C which has been associated with lower risk of heart disease, like atherosclerosis.3 Boost your heart health by adding tangerines to your spinach salad and quadruple the amount of iron you absorb.

Green Tea

Researchers estimate the rate of cardiac arrest decreases by 11% with consumption of three cups of tea per day.4 Green tea is rich in Theanine, the amino acid that will offset caffeine’s effect.

Tomatoes

Cardio-protective functions provided by the nutrients in tomatoes may include the reduction of low-density lipoprotein (LDL) cholesterol, homocysteine, platelet aggregation, and blood pressure.5 Go local and organic with this fruit in particular.

Extra Virgin Olive Oil

Rich in monounsaturated fats (MUFAs), EVOO may help lower your risk of heart disease by improving related risk factors. For instance, MUFAs have been found to lower your total cholesterol and low-density lipoprotein cholesterol levels.6  Promote heart health by upping your intake of this delicious fat in favor of relying too heavily on nuts.

Spinach

Lutein (a carotenoid); B-complex vitamins; Folate; magnesium; potassium; calcium; fiber.7  Looks like Popeye had the right idea!

Avocados

Consumption of ½ – 1½ avocados a day may help to maintain normal serum total cholesterol. More evidence that good fat is good!8

Wine (Sulfite-Free)

Rich in resveratrol, studies have shown that adults who drink light to moderate amounts of alcohol may be less likely to develop heart disease than those who do not drink at all or are heavy drinkers.9  Cheers to that!

Dark Chocolate

In humans, flavanol-rich cocoa counteracts lipid peroxidation and, therefore, lowers the plasma level.10  Just make sure to stick to the real stuff and go as close to 100% cacao as you can find!

And, just in time for Valentine’s Day, why not use this as the special occasion to enjoy my signature Paleo truffles!

While it’s no surprise wild salmon and leafy greens are included in my list of Top 10 Paleo Foods, when there’s room for the occasional glass of red wine and raw, dark chocolate on a lifelong Paleo regime too, it’s something that many people, myself included, enjoy wholeheartedly.

 

REFERENCES

[1] “The Role of Fish Oil in Arrhythmia Prevention”, Anand RG, Alkadri M, Lavie CJ, Milani RV. Mar-Apr 2008

[2] “Daily Blueberry Consumption Improves Blood Pressure and Arterial Stiffness in Postmenopausal Women with Pre- and Stage 1-Hypertension: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial”, Sarah A. Johnson, PhD, RD, CSO, Arturo Figueroa, MD, PhD, FACSM, Negin Navaei, Alexei Wong, PhD, Roy Kalfon, MS, Lauren T. Ormsbee, MS, Rafaela G. Feresin, MS, Marcus L. Elam, MS, Shirin Hooshmand, PhD, Mark E. Payton, PhD, Bahram H. Arjmandi, PhD, RD, October, 2014

[3] Woollard KJ, Loryman CJ, Meredith E, et al. Effects of oral vitamin C on monocyte: endothelial cell adhesion in healthy subjects. Biochem Biophys Res Commun. 2002 Jun 28;294(5):1161-8.

[4] Cooper R, Morre DJ, Morre DM. Medicinal benefits of green tea: Part I. Review of noncancer health benefits. J Altern Complement Med. 2005;11(3):521-8.

[5] Crit Rev Food Sci Nutr. 2003;43(1):1-18. Tomatoes and cardiovascular health. Willcox JK1, Catignani GL, Lazarus S.

[6] Lecerf JM. Fatty acids and cardiovascular disease. Nutrition Reviews. 2009;67:273.

[7] Ursula Arens, dietetician at the British Dietetic Association, Kathleen Zelman, WebMD director of nutrition. U.S. Highbush Blueberry Council. British Heart Foundation. British Dietetic Association. The Journal of the American Medical Association , July 23/30, 2003.

[8] Influence of avocados on serum cholesterol.[Proc Soc Exp Biol Med. 1960]

[9] Brien SE, Ronksley PE, Turner BJ, Mukamal KJ, Ghali WA. Effect of alcohol consumption on biological markers associated with risk of coronary heart disease: systematic review and meta-analysis of interventional studies. BMJ. 2011;342:d636.

[10] Wiswedel I, Hirsch D, Kropf S, Gruening M, Pfister E, Schewe T, Sies H. Flavanol-rich cocoa drink lowers plasma F(2)-isoprostane concentrations in humans. Free Radic Biol Med. 2004; 37: 411–421.

Seafood Mercury Concerns Subside Amid New Research | The Paleo Diet

Fish and other marine life have been integral to human diets since the Paleolithic era. Some researchers even speculate that these foods “made us human” by enabling the rapid expansion of grey matter in the cerebral cortex. For three million years of evolution during the time of Australopithecus, brain capacity remained constant, but then curiously doubled during a one-million-year period between Homo erectus and Homo sapiens.1 The reasons for this great expansion are not entirely known, but increased dietary omega-3 from fish and shellfish was likely involved.

Fish consumption remains critically important today, but comes with complications unimaginable to our distant ancestors. Industrial pollution has greatly increased environmental mercury, much of which ends up in oceans and lakes, and finally, in small amounts, in the bodies of fish. In higher amounts, mercury is toxic and is especially problematic for developing babies. For years, the FDA was advising pregnant women to limit their fish consumption during pregnancy, but last year, they issued a draft revision encouraging prenatal fish consumption.2 This draft, which will eventually replace their previous recommendations, reflects a growing awareness, seen in the scientific literature, that fish is essential for developing babies and contains nutrients that limit, or even counter, the potentially harmful effects of mercury.

Recently published in the American Journal of Clinical Nutrition, a new study, representing 30 years of research in the Seychelles, is one of the longest and largest population studies regarding seafood and mercury.3 The Seychelles is a nation of islands clustered together in the Indian Ocean, where residents consume 10 times as much seafood as do Europeans and Americans, making it an ideal place to study the long-term impact of mercury exposure via seafood. The researchers concluded that high fish consumption by pregnant mothers, as much as 12 meals per week (the FDA recommends three), does not cause developmental problems in children.

To the contrary, fish is extremely beneficial for development, and contains special nutrients that protect against mercury. Lead author Dr. Sean Strain explained, “This research provided us the opportunity to study the role of polyunsaturated fatty acids [PUFAs] on development and their potential to augment or counteract the toxic properties of mercury.”4 Mercury is thought to damage the brain through oxidation and corresponding inflammation. Fish are rich in omega-3 PUFAs, which prevent inflammation, as opposed to omega-6 PUFAs, which promote inflammation. This was reflected in the study whereby children of mothers who had higher omega-6 blood levels performed worse on tests designed to measure motor skills.

This study builds upon an impressive body of research conducted by Dr. Nicholas Ralston and colleagues at the University of North Dakota. Ralston has demonstrated that selenium also protects against mercury toxicity and that foods with relatively higher amounts of selenium with respect to mercury, pose neither developmental nor neurological risks based on mercury toxicity.5 “This may explain,” Ralston says, “why studies of maternal populations exposed to foods that contain Hg [mercury] in molar excess of Se [selenium], such as shark or pilot whale meats, have found adverse child outcomes, but studies of populations exposed to MeHg [methylmercury] by eating Se-rich ocean fish observe improved child IQs instead of harm.”6

The vast majority of commonly consumed fish and shellfish contain far more selenium relative to mercury and many have significant amounts of omega-3 PUFAs. This means that fish and shellfish, two important components of the Paleo diet, should not be limited nor discontinued based on mercury concerns. Whether for pregnant women, babies, children, or adults, we encourage you to keep seafood on the menu.

Christopher James Clark, B.B.A.

@nutrigrail
Nutritional Grail
www.ChristopherJamesClark.com

Christopher James Clark | The Paleo Diet TeamChristopher James Clark, B.B.A. is an award-winning writer, consultant, and chef with specialized knowledge in nutritional science and healing cuisine. He has a Business Administration degree from the University of Michigan and formerly worked as a revenue management analyst for a Fortune 100 company. For the past decade-plus, he has been designing menus, recipes, and food concepts for restaurants and spas, coaching private clients, teaching cooking workshops worldwide, and managing the kitchen for a renowned Greek yoga resort. Clark is the author of the critically acclaimed, award-winning book, Nutritional Grail.

REFERENCES

[1] Bradbury, J. (May 2011). Docosahexaenoic Acid (DHA): An Ancient Nutrient for the Modern Human Brain. Nutrients, 3(5). Retrieved from //www.ncbi.nlm.nih.gov/pmc/articles/PMC3257695/

[2] U.S. Food and Drug Administration. (June 2014). Fish: What Pregnant Women and Parents Should Know. Draft Updated Advice by FDA and EPA. Retrieved from //www.fda.gov/Food/FoodborneIllnessContaminants/Metals/ucm393070.htm

[3] Strain, JJ, et al. (January 2015). Prenatal exposure to methyl mercury from fish consumption and polyunsaturated fatty acids: associations with child development at 20 mo of age in an observational study in the Republic of Seychelles. American Journal of Clinical Nutrition, 101(1). Retrieved from //ajcn.nutrition.org/content/early/2015/01/21/ajcn.114.100503

[4] University of Rochester Medical Center. (January 21, 2015). Fatty acids in fish may shield brain from mercury damage. ScienceDaily. Retrieved from www.sciencedaily.com/releases/2015/01/150121144835.htm

[5] Ralston, NV and Raymond, NJ. (November 2010). Dietary selenium’s protective effects against methylmercury toxicity. Toxicology, 278(1). Retrieved from //www.ncbi.nlm.nih.gov/pubmed/20561558

[6] Ibid, Ralston.

Paleo Diet Primer: Fats and Oils | The Paleo Diet

When it came to fats and oils, the choice was simple for our hunter gatherer ancestors. All dietary fats were consumed directly from the food source and were based on their geographic availablity. They ate the whole carcass of wild animals, including all of the organs and visceral fat, and foraged for fatty, high oil plants. These foods balanced the fatty acids in their diet. Today, as technology engineers oils from vegetable seeds, like mustard seed, cottonseed, and rapeseed (canola) oil, not only is the yield unnatural, it is also unsafe for consumption.

All animal fats, such as lard, tallow, duck and chicken fat, can withstand very high temperatures without oxidizing,1 and have prolonged shelf lives. However, navigating the bottled oil aisle at any grocery store can overwhelm even the most advanced label reader to decipher which  oils are safe and optimal for health.  A thorough explanation of the fatty acid composition of vegetables oils, as well as identifying the six vegetable oils (flaxseed, walnut, olive, macadamia, coconut, and avocado)  that are best suited for the Paleo Diet can be found HERE.  Yet, many of us still struggle with which cooking oil to select and how to heat it without compromising the nutritious benefits.

When heating any oil, it is important to keep them below their smoke point, (before oil burns to the point of smoking). Oils heated above their stability point begin to decompose, releasing free radicals along with toxic fumes. Oils are often refined to raise their smoke point. The refining process (heating, neutralization, filtering, and processing with chemicals and bleaching agents) removes the  oils from their pure state.2 Thus, despite their lower smoke point, unrefined virgin oils are preferential.

Flaxseed oil

If we look to hunter-gather-societies, we see they did not regularly use flaxseed oil. It was originally included in The Paleo Diet as a tool to balance out increased omega-6/omega-3 fatty acid ratio due to the excessive intake of omega-6 vegetable oils, especially linoleic acid, in the average western diet. Flaxseed oil is exceptionally high in alpha-linolenic acid (ALA), which is the parent fatty acid to Omega-3 fatty acids. Omega-3 fatty acids are extremely sensitive to heat, oxygen, and light,3 so refrigerate and never heat, but instead use in a salad dressing or as a finishing oil over cool vegetables.

Walnut Oil

Walnut oil possesses many antioxidants, including ellagic acid, which research suggests is antiatherogenic and supports osteoblastic activity.4 It’s a great source of omega-3 fatty acids 5 and although the refined version is often labeled safe for high-heat cooking, it is best not to heat it to high temperatures. Not only will the omega-3s be damaged, but the oil will also develop a bitter taste. The unrefined version can be heated to 320°F,6 so sauté vegetables in walnut oil  at low-to-medium heat, or drizzle on any salad.

Extra-Virgin Olive Oil

Olive oil contains at least 30 phenolic compounds.7 Phenols have been shown to reduce the amount of oxidative stress on the body8 and  protect the polyunsaturated fat in the olive oil from oxidizing. Olive oil is a great source of healthy monounsaturated fats, which help control cholesterol levels and have been linked with heart health. There are many varieties of olive oils, sourced from all over the world. Each has its own unique flavor and color that can be experimented with to highlight whatever dish you are cooking. And, while extra virgin olive oil has a smoke point of 325°F,9 it is fairly resistant to oxidation, even when used for high-heat deep-frying.10, 11

Macadamia Nut Oil

Macadamia nut oil is higher in monounsaturated fats than olive oil12 and provides the lowest level of omega-6 fats of any nut.13 It is high in phytochemicals, (qualene, tocotrienols and tocopherols), which protect against oxidation, making it suitable for room temperature storage for up to two years.14 Macadamia nut oil has been shown to improve the biomarkers of oxidative stress, inflammation, and reduce the risk factors for coronary artery disease.15

With a smoke point of 413°F, 16 macadamia oil can be used for almost any dish whether you’re grilling, sautéing or stir-frying. It can even be used a binder for homemade Paleo mayonnaise.

Coconut Oil

Coconut oil is more than 90% saturated fat; specifically it is high in medium chain triglyceride (MCT). MCTs do not require bile acids for digestion, which makes them easy to digest and available immediately as a fuel source.17 Coconut oil is also rich in lauric acid, a fatty acid found in mother’s milk that has anti-fungal, anti-bacterial and anti-viral properties.18 Unrefined coconut oil, which has not been bleached or filtered to remove impurities or natural flavors, has a smoke point of 320°F.19

Coconut oil, which is solid at room temperature, can be used as a replacement in any recipe that calls for butter, such as for coating a whole chicken before roasting. It also works well with Caribbean or Asian recipes, especially to those who aren’t quite accustomed to the flavor. We use it regularly to sauté vegetables, like kale or onions, as well as to grease the pan for cooking eggs.

Avocado oil

Avocados, thought classified as a fruit, are high in oil content. Cold pressing of avocados retains a high concentrations of vitamin E 20 and chlorophyll (40-60mg/kg), which gives the oil a green tint. 21 Research shows consuming avocado oil enhances carotenoid absorption from vegetables,22 and can decrease your risk of coronary artery disease.23 Similar to olive oil, avocado oil has a higher Omega 6:3 ratio (13.1:1).24 Avocado oil can withstand the heat. Virgin (unrefined) avocado oil has a smoke point of 40025 and can be used in any high heat cooking, dressing or as a finishing oil.

 

REFERENCES

[1] Sherwin, E. R. Oxidation and antioxidants in fat and oil processing. Journal of the American Oil Chemists’ Society 55.11 (1978): 809-814.

[2] Available at: //www.business2community.com/health-wellness/the-danger-of-cooking-with-healthy-oils-past-their-smoke-point-0418150. Accessed on October 28, 2014.

[3] Choo, W. S., E. J. Birch, and J. P. Dufour. Physicochemical and stability characteristics of flaxseed oils during pan-heating. Journal of the American Oil Chemists’ Society 84.8 (2007): 735-740.

[4] Papoutsi, Z., et al. Walnut extract (Juglans regia L.) and its component ellagic acid exhibit anti-inflammatory activity in human aorta endothelial cells and osteoblastic activity in the cell line KS483. British journal of nutrition 99.04 (2008): 715-722.

[5] Available at: //www.hsph.harvard.edu/nutritionsource/omega-3/.  Accessed on October 28, 2014.

[6]Available at: //www.goodeatsfanpage.com/collectedinfo/oilsmokepoints.htm. Accessed on October 28, 2014

[7] Tuck, Kellie L., and Peter J. Hayball. Major phenolic compounds in olive oil: metabolism and health effects. The Journal of nutritional biochemistry 13.11 (2002): 636-644.

[8] Kim, Hwa-Young, Ok-Hee Kim, and Mi-Kyung Sung. Effects of phenol-depleted and phenol-rich diets on blood markers of oxidative stress, and urinary excretion of quercetin and kaempferol in healthy volunteers. Journal of the American College of Nutrition 22.3 (2003): 217-223.

[9]Available at: //culinaryarts.about.com/od/culinaryreference/a/smokepoints.htm. Accessed on October 28, 2014.

[10] Casal, Susana, et al. Olive oil stability under deep-frying conditions. Food and Chemical Toxicology 48.10 (2010): 2972-2979.

[11] Sutherland, Wayne HF, et al. Effect of meals rich in heated olive and safflower oils on oxidation of postprandial serum in healthy men. Atherosclerosis 160.1 (2002): 195-203.

[12] Ako, H, Okuda D, and Gray D. Healthful new oil from macadamia nuts. Nutrition (Burbank, Los Angeles County, Calif.) 11.3 (1995): 286.

[13] Avaialable at: //blog.lluniversity.com/nuts-and-oils-why-coconut-and-macadamia-nut-are-king/. Accessed on October 28, 2014.

[14] Wall, Marisa M. Functional lipid characteristics, oxidative stability, and antioxidant activity of macadamia nut (Macadamia integrifolia). Food chemistry 121.4 (2010): 1103-1108.

[15] Garg, Manohar L, et al. Macadamia nut consumption modulates favourably risk factors for coronary artery disease in hypercholesterolemic subjects. Lipids 42.6 (2007): 583-587.

[16] Available at: //www.naturalnews.com/029202_olive_oil_smoke_point.html.  Accessed on October 14, 2014.

[17] Prior, IA, et al. “Cholesterol, coconuts, and diet on Polynesian atolls: a natural experiment: the Pukapuka and Tokelau island studies.” The American journal of clinical nutrition 34.8 (1981): 1552-1561.

[18] Isaacs, CE, et al. “Antiviral and antibacterial lipids in human milk and infant formula feeds.” Archives of Disease in Childhood 65.8 (1990): 861-864.

[19] Available at: //www.livestrong.com/article/446041-is-coconut-oil-good-for-frying-on-high-temperature-cooking/. Accessed on October 28, 2014.

[20] Eyres L, Sherpa N and Hendriks G. Avocado oil: a new edible oil from Australasia. Lipid Technol 2001;Vol 13, no 4:84-88.

[21] Swisher, Horton E. Avocado oil. J Am Oil Chem 65 (1988): 1705.

[22] Unlu, Nuray Z., et al. “Carotenoid absorption from salad and salsa by humans is enhanced by the addition of avocado or avocado oil.” The Journal of nutrition 135.3 (2005): 431-436.

[23] Watts GF, Lewis B, Brunt JNH, Lewis ES, Coltart DJ, Smith LDR, Mann JI and Swan AV. Effects on coronary artery disease of lipid-lowering diet, or diet plus cholestyramine, in the St Thomas’ Atherosclerosis Regression Study (STARS). Lancet 1992;339:563-569.

[24] Available at: https://theconsciouslife.com/omega-3-6-9-ratio-cooking-oils.htm. Accessed on October 28. 2014.

[25] Available at: //www.vegkitchen.com/tips/avocado-oil-expeller-pressed-naturally-refined/attachment/smoke-point-chart/. Accessed on October 28, 2014.

Vegetarian Diet | The Paleo Diet

Did you miss Vegetarian and Vegan Diets: Nutritional Disasters Part 1 or Part 2?
Read Part 1 HERE
Read Part 2 HERE

Vegetarian Diets: Other Nutritional Shortcomings

You don’t have to look any further than the ADA’s Position Statement28 or the USDA’s recommendations on vegetarian diets142 to discover additional nutrient shortcomings caused by plant based diets. The ADA matter of factly mentions that “…key nutrients for vegetarians include protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B12..28 The USDA notes that “…vegetarians may need to focus on…iron, calcium, zinc, and vitamin B12.142 These subtle admissions of potential nutrient deficiency problems associated with vegetarian diets represent the tip of a nutritional nightmare. Just as was the case with vegetarian diets and vitamin B12 deficiency, there is little credible scientific evidence to show that people eating a lifelong plant based diet (without taking supplements or eating fortified foods) can achieve adequate dietary intakes of omega 3 fatty acids (EPA and DHA), iron, zinc, iodine, calcium, and vitamin D. To this list you can also add vitamin B6 and taurine, an amino acid.

Mineral Deficiencies and Vegetarian Diets

One of the major complications with the assessment of dietary nutrient adequacy in vegetarian diets, or for that matter, any diet has to do with whether or not the vitamins and minerals measured in certain foods actually get absorbed into our bodies. The bioavailability of vitamins and minerals in foods is just as important in how they impact our health as is the simple content of these nutrients in a food. By now you know that phytate is not a good thing because it prevents absorption of essential minerals. Whole grains and legumes are rich sources of phytate. Accordingly, our bodies have great difficulty extracting certain minerals from these foods because they are tightly bound to phytate. Phytate in whole grains impairs calcium absorption and may adversely affect bone health. Further, phytate also binds zinc, thereby interfering with its assimilation and incorporation into our cells. To this list you can add iron and magnesium. Because vegetarian diets are virtually impossible to follow without including lots of whole grains, beans, soy and legumes, they are inherently high in phytate. This is why it is difficult or impossible for vegetarians and vegans to maintain adequate body stores of calcium, zinc and iron.

Zinc Deficiencies in Vegetarian Diets

From the discussion above, you know that zinc is crucial for normal male reproductive function, but it is also required for good health and disease resistance in virtually every cell in our bodies, whether you are a man, woman or child.20, 41 Marginal zinc status impairs our immune system, slows wound healing, adversely affects glucose and insulin metabolism, and damages our body’s built in antioxidant system.16, 55 Without adequate dietary zinc we experience more upper respiratory illnesses that last longer. Zinc lozenges can slow or prevent common cold symptoms, and zinc oxide creams applied topically can speed healing. If you have ever experienced painful cracked heels or nose bleeds that just wouldn’t stop, try rubbing zinc oxide ointments on these wounds – you will be amazed at how rapidly zinc can heal these stubborn sores. How we got into this problem (marginal zinc status or deficiencies) in the first place originates directly from our diets. Anybody eating excessive whole grains and/or legumes and not eating meat, fish or animal products on a regular basis45, 59, 62 puts themselves at risk for all illnesses and health problems associated with borderline or deficient zinc intakes.

Iron Deficiencies in Vegetarian Diets

Your body stores of iron run hand in hand with zinc. The same types of diets that produce zinc deficiencies also create iron deficiencies. High phytate vegetarian diets based upon whole grains, beans, soy and other legumes invariably cause iron deficiencies5, 135 which are the most common nutrient deficit worldwide. In the U.S. 9% of all women between 12 and 49 years are iron deficient, while 4% of 3 to 5 year old children have insufficient stores of this crucial mineral.25 If you are pregnant, low iron status increases your risk of dying during childbirth, and frequently causes low birth weights and preterm deliveries. Even more disturbing is the potential for iron deficiencies to prevent normal mental development in our children and young adults.39, 90, 96 As a parent, I would never wish upon my child or for that matter anyone else’s, a diet causing nutritional deficiencies known to impair brain development and normal mental function. But this is just the case if you eat a vegetarian diet and impose it upon your children. Plant based diets not only increase the risk of impaired cognitive function in your children, but will hamper your own mental functioning. Numerous experimental studies show that inadequate iron stores in adults can slow or impair tasks requiring concentration and mental clarity.73

One of the most important outcomes of diets that cause iron deficiencies is that they make us fatigued and tired. If you are an athlete or have a demanding job requiring physical exertion, low iron stores will invariably reduce your performance. A recent (2009) experiment involving 219 female soldiers during military training showed that iron supplements improved blood iron stores, increased performance for a 2 mile run and enhanced mood.92 Similarly a study by Dr. Hinton and colleagues demonstrated that iron supplements in iron deficient male and female athletes improved endurance performance and efficiency.56 Whether you are an athlete, a laborer or even an office worker, your best nutritional strategy to improve iron stores, add vigor to your life and improve performance is to eliminate whole grains and legumes from your diet by adopting The Paleo Diet.

The burden of proof that vegetarian diets will not produce multiple vitamin and mineral deficiencies lies upon the governmental (USDA) and dietary organizations (ADA) that recommend these diets to us all and tell us that they are safe.28, 142 You might expect that the experimental evidence surrounding vegetarian diet recommendations would be convincing and overpowering. Nothing could be further from the truth, particularly when it comes to iron deficiencies and vegetarian diets.

As always the devil is in the details when it comes to getting correct answers to nutritional questions. Scientists who believe that vegetarian diets don’t adversely affect our iron stores often cite scientific papers showing no difference between blood iron concentrations in vegetarians and meat eaters. What they don’t tell us is how iron measurements were performed in the experiments they quote to support their viewpoint. This information is absolutely essential in knowing if iron deficiencies exist or not. Any study examining blood levels of iron in vegetarians using either measurements of hemoglobin (an iron carrying substance in red blood cells) or hematocrit (the concentration of red blood cells) are unreliable indicators of long term iron status. A much better marker is an iron carrying molecule called ferritin.75 Virtually all epidemiological (population) studies of vegans or ovo/lacto vegetarians show them to be either deficient or borderline iron deficient when blood ferritin levels are measured. Given this nearly unanimous finding from epidemiological studies, you might think that either the USDA or the ADA would become concerned and re-examine their endorsement of vegetarian diets. Unfortunately, we still live with governmental and institutional dietary recommendations that may do considerable harm to our health.

The most convincing type of experiments to reveal whether or not vegetarian diets may cause our iron stores to nosedive are called dietary interventions. Why not put a large group of non-vegetarians on a plant based diet for an extended period and see what happens to their blood iron levels? Wow what a great idea – unfortunately no such study has ever been conducted. The closest we have come to this experiment is a short term study (8 weeks) by Dr. Janet Hunt and co-workers at the Grand Forks Human Nutrition Research Center in North Dakota.63 The results of this experiment were anything but conclusive as the researchers made a fundamental blunder in the design of their experiment – they forgot to include a control group. Without a control group, it is impossible to interpret the outcome of this or any experiment.

Nevertheless, when women were placed on lacto/ovo vegetarian diets, their intestinal iron absorption was reduced by 70%; however, inexplicably, blood ferritin levels (a marker of their long-term iron status) did not decline for the group as a whole. It should be noted that nearly half of the subjects did experience drops in blood ferritin concentrations. Because the authors of this study failed to include a control group, then extraneous variables likely swayed the experiment’s outcome. You recall from earlier in this essay that vegetarian diets caused 7 out of 9 women to stop ovulating. With the cessation of menstrual periods, monthly blood loses also cease which in turn prevents monthly iron losses because blood is a rich source of iron. Hence, in any study evaluating blood iron stores in women, it is absolutely essential to know if their normal menstrual cycles were altered. Unfortunately, Dr. Hunt did not provide us with this information, thereby making the correct interpretation of her experiment difficult or impossible.

In order to once and for all know whether or not vegetarian diets cause iron deficiencies, we would need to perform Dr. Hunt’s experiment again, for at least a year with more subjects, a control group and monitor changes in menstrual periods. You would think that this kind of very basic experimental evidence would have already been in place before any governmental or institutional organization told us that vegetarian diets were safe and didn’t cause nutritional deficiencies. Unfortunately, these precautionary steps have never been taken, and millions of Americans who adhere to vegetarian diets with the mistaken belief that they will benefit health-wise will actually suffer.

Iodine Deficiencies in Vegetarian Diets

A number of studies have reported that vegetarian and vegan diets increase the risk for iodine deficiency.40, 77, 102, 153 One study from Europe demonstrated that 80% of vegans and 25% of ovo/lacto vegetarians suffered from iodine deficiency.77 Additionally, a dietary intervention by Dr. Remer and colleagues in 1999 confirmed this epidemiological evidence.102 After only five days on ovo/lacto vegetarian diets, iodine status and function became impaired in healthy adults.102 The primary reason why vegetarian diets cause iodine deficiencies is that plant foods (except for seaweed) are generally poor sources of iodine compared to meat, eggs, poultry and fish. Gross deficiencies of iodine cause our thyroid glands to swell producing a condition known as goiter, and in pregnant women result in severe birth defects called cretinism.141 Because salt is fortified with iodine, most people in the U.S. and Europe rarely develop gross iodine deficiencies.40, 140, 141 However moderate to mild iodine deficiencies appear in westernized countries, particularly among vegetarians and vegans.77, 102 Moderate iodine deficiency impairs normal growth in children and adversely affects mental development.140, 141, 152 A large meta analysis revealed that moderate childhood iodine deficiency lowered I.Q. by 12-13.5 points.153 Paleo Diets are not just good medicine for adults, but they also ensure normal physical and mental development in our children because of their high iodine content.

One of the problems with plant based diets is that they may put into play a vicious cycle that makes iodine deficiencies worse. When the thyroid glands iodine stores become depleted, as often happens with vegetarian diets, then certain antinutrients found in plant foods can gain a foot hold and further aggravate iodine shortages. Soy beans and soy products are frequently a mainstay in vegetarian diets and may promote inflammation.66 Unfortunately soy contains certain antinutrients (isoflavones) that impair iodine metabolism in the thyroid gland,43, 95 but only when our body stores of iodine are already depleted. Other plant foods (millet, cassava root, lima beans, sweet potatoes, and cruciferous vegetables [broccoli, cauliflower, turnips, kale, cabbage]) also contain a variety of antinutrients which hinder normal iodine metabolism. So, plant based diets put us at risk for developing iodine deficiencies in the first place, and when this happens our bodies become vulnerable to plant antinutrients that worsen the pre-existing deficiency. The important point here is that antinutritional compounds have virtually zero effect upon our thyroid gland when our body stores of iodine are normal and fully replete. Because meats, fish, eggs and poultry are rich sources of iodine, you will never have to worry about this nutrient when you eat Paleo style.

Vitamin D and Vitamin B6 Deficiencies in Vegetarian Diets

In my paper, Cereal Grains: Humanity’s Double Edged Sword, I have pointed out how excessive consumption of whole grains adversely affects vitamin D status in our bodies.148 Hence it goes without saying that vitamin D deficiencies run rampant in vegetarians worldwide because it is nearly impossible to become a full-fledged vegetarian without eating lots of grains. In the largest study of vegetarians ever undertaken (The Epic-Oxford Study), Dr. Crowe and fellow researchers reported that blood concentrations of vitamin D were highest in meat eaters and lowest in vegans and vegetarians.29 Nearly 8% of the vegans maintained clinical deficiencies of vitamin D. Vitamin D is not really a vitamin at all, but rather a crucial hormone that impacts virtually every cell in our bodies.

By now, you are starting to get a pretty good picture of what a nutritional nightmare vegetarian diets really are. When we let the data speak for itself, the number of nutrient deficiencies and adverse health effects associated with plant based diets are appalling and far outweigh any supposed health effects of this unnatural way of eating. One of the biggest kept secrets about vegan or vegetarian diets is that they frequently cause vitamin B6 deficiencies. If you recall, neither the ADA,28 nor the USDA142 has given us any warning that meatless diets increase our risk for vitamin B6 deficiencies.

On paper, it would appear that vegetarian diets generally meet daily recommended intakes for vitamin B6. This assumption comes primarily from population surveys examining the foods that vegans and vegetarians normally eat. In contrast, when blood samples are analyzed from people relying upon plant based diets, they unexpectedly reveal that long term vegetarians and vegans frequently are deficient vitamin B6. A recent study of 93 German vegans by Dr. Waldman and colleagues showed that 58% of these men and women suffered from vitamin B6 deficiencies despite seemingly adequate intakes of this essential nutrient.131 It turns out that the type of vitamin B-6 (pyridoxine glucoside) found in plant foods is poorly absorbed.47, 103 The presence of pyridoxine glucoside in plant foods along with fiber has been reported to reduce the bioavailability of vitamin B6 so that only 20 to 25% is absorbed and completely utilized.47 In contrast, vitamin B6 found in animal foods is easily assimilated, and an estimated 75 to 100% fully makes its way into our bloodstreams.47

Compelling evidence that vegetarian diets relying upon the plant form of vitamin B6 adversely affect our body’s overall vitamin B6 stores comes from Dr. Leklem’s laboratory at Oregon State University.47 Nine women were put on diets either high or low in the plant form of vitamin B6 (pyridoxine glucoside). After only 18 days, the high pyridoxine glucoside diets consistently lowered blood concentrations and other indices of vitamin B6 status. Deficiencies in this vitamin elevate blood homocysteine concentrations and increase our risk for cardiovascular disease similar to shortages of folate and vitamin B12. Further, vitamin B6 is an important factor in normal immune system functioning149 and shortfalls of this crucial nutrient have been identified in depression150 and colorectal cancer.151

Omega 3 Fatty Acid Deficiencies in Vegetarian Diets

A few years ago I was involved in a series of experiments here at Colorado State University in which we were interested in determining how high and low salt diets affected exercise-induced asthma. Our working hypothesis was that high salt diets would make measures of lung function worse, and low salt diets would improve things. One of our concerns with this experiment was to somehow make sure our subjects had fully complied with either the high or low salt diets. Completely removing salt from your diet is not an easy thing to do, and if some of our subjects had decided to sneak in a piece of pizza or some Doritos, it would mess up the experiment’s outcome. Fortunately, there was an easy way to figure out if our subjects had been compliant with the prescribed diets. All we had to do was to spot check their urine, because measurement of urinary salt levels is an accurate gauge of dietary salt consumption. High urinary salt levels universally reflect high salt consumption, whereas low urinary salt concentrations indicate low salt consumption. Short of major disease, there is virtually no other way high amounts of salt in the urine don’t indicate high amounts of salt in the diet.

In a similar manner, there are equivalent telltale indicators of omega 3 fatty acids in our bloodstreams that tell us beyond a shadow of a doubt whether or not we have regularly consumed fish, seafood or other good sources these healthful fats. The three main types of omega 3 fatty acids we need to concern ourselves with are EPA, DHA and ALA. EPA and DHA are called long chain omega 3 fatty acids and are only found in high amounts in fish, seafood, certain meats, and other foods of animal origin. Plant foods contain no EPA or DHA. On the other hand, ALA is called a short chain fatty acid and is found in both plant and animal foods. Both EPA and DHA in our red blood cells are markers of these important fatty acids in our diet. Without good dietary sources of EPA and DHA such as are found in fish, seafood and certain meats, our blood levels of EPA and DHA will decline. Just like salt in our urine was an indicator for dietary salt, EPA and DHA concentrations in our red blood cells are markers for our dietary intake of these long chain omega 3 fatty acids. It is virtually impossible to achieve high blood levels of EPA and DHA without regularly consuming fish, seafood and certain meats and organ meats (particularly grass produced meats and organ meats).

One of the major nutritional shortcomings in vegans is that they obtain absolutely no EPA or DHA from their diets.108, 110, 111 Consequently, they are totally dependent upon plant based ALA, supplements or fortified foods to obtain these healthful long chain omega 3 fatty acids. Without supplements or fortified foods, all vegans will become deficient in EPA and DHA because plant based ALA is inefficiently converted into these long chain fatty acids in our bodies. The liver converts less than 5% of ALA into EPA and less than 1% of ALA into DHA.15, 97 Virtually every epidemiological study that has ever been published shows that vegans, who do not supplement or consume long chain omega 3 fortified foods, to be deficient in both EPA and DHA76, 88, 108, 110, 111 Lacto/ovo vegetarians don’t fare much better because milk and egg based vegetarian diets simply do not supply sufficient DHA or EPA to maintain normal blood concentrations.88, 111

There is little doubt that vegan or vegetarian diets cause reductions in blood concentrations of DHA and EPA, which in turn represent a potent risk factor for many chronic diseases. Perhaps the single most important dietary recommendation to improve your health and prevent illness is to increase your dietary intake of EPA and DHA. Thousands of scientific papers covering an assortment of diseases clearly show the health benefits of these fatty acids. In randomized clinical trials in patients with pre-existing heart disease, omega-3 fatty acid supplements significantly reduced cardiovascular events (deaths, non-fatal heart attacks, and non-fatal strokes).19, 48, 138 Omega-3 fatty acids lessen the risk for heart disease through a number of means including a reduction in heart beat irregularities called arrhythmias, a decrease in blood clots, and reduced inflammation which is now known to be an chief factor causing atherosclerosis or artery clogging.

In addition to lowering the risk for heart disease, regular consumption of fish or supplemental omega-3 fatty acids may be useful in averting, treating, or improving a wide range of diseases and disorders, including virtually all inflammatory diseases (any disease ending with “itis”): rheumatoid arthritis,99 inflammatory bowel disorders (Crohn’s disease, ulcerative colitis), periodontal disease (gingivitis). Also mental disorders (autism, depression),3, 84 postpartum depression, bi-polar disorder, borderline personality disorder, impaired cognitive development in infants and children) may respond favorably to these beneficial fatty acids. Further, acne, asthma, exercise induced asthma, many types of cancers,120 macular degeneration, pre-term birth, psoriasis, insulin resistance, type 2 diabetes, cancer cachexia, intermittent claudication, skin damage from sunlight, IgA nephropathy, lupus erythematosus, type 1 diabetes, multiple sclerosis, and migraine headaches also improve with omega 3 fatty acids.

Taurine deficiencies in Vegetarian Diets

Although the number of nutrients which are frequently lacking in vegetarian and vegan diets may seem endless to you, we are now at the end of the list. Taurine is an amino acid (actually a sulfonic acid because it lacks a carboxyl group) in our bloodstreams that has multiple functions in every cell of our body. Unfortunately, this nutrient is not present in any plant food and is found in low concentrations in milk (6 mg per cup).80 In contrast, all flesh foods are excellent sources of taurine.80 For example, ¼ pound of dark meat from chicken provides 200mg of taurine. Shellfish are even richer still with over 800mg per quarter pound. The daily taurine intake in non-vegetarians is about 150mg, whereas lacto/ovo vegetarians take in about 17mg per day, and vegans get none. Although our livers can manufacture taurine from precursor molecules, our capacity to do so is limited – so much so that this amino acid is regularly fortified in infant formulas. As you might expect, studies of vegans show that their blood taurine levels are lower than meat eaters.81, 100 How depleted blood concentrations of taurine affect our overall health, is not entirely understood. Nevertheless, shortages of this amino acid and omega 3 fatty acids (EPA and DHA) may cause certain elements (platelets) in our blood to clot more rapidly which in turn increase our risk for cardiovascular disease.85, 91 Despite their meat free diets, vegetarians almost always exhibit abnormal platelets that excessively adhere to one another. In one dietary intervention, Dr. Mezzano and colleagues demonstrated that after eight weeks of EPA and DHA supplementation normal platelet function was restored in a group of 18 lacto/ovo vegetarians.85 Obviously, compromised taurine status will never become a problem in Paleo Diets, because meat, fish, poultry and animal products are consumed at nearly every meal.

In summary, if you have adopted, or are considering adopting a plant based diet for reasons of improving your health, make sure you reread this chapter and look up all of the references I have provided you. The evidence that vegetarian and vegan diets almost always cause a multitude of nutritional deficiencies is overwhelming and conclusive. Over the course of a lifetime, vegetarian diets will not reduce your risk of chronic disease and will not allow you to live longer. Rather, this abnormal way of eating will predispose you to a host of health problems and illnesses. Vegetarianism is an unnatural way of eating that has no evolutionary precedence in our species. No hunter-gatherer society ever consumed a meatless diet, nor should you. The ADA has labeled The Paleo Diet a fad diet because it eliminates “two entire food groups” (grains and dairy). Yet hypocritically, they exempt vegan diets from this characterization despite also eliminating two food groups (dairy, meats and fish). If The Paleo Diet is a fad diet, then it is the world’s oldest.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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110. Sanders TA, Roshanai F. Platelet phospholipid fatty acid composition and function in vegans compared with age- and sex-matched omnivore controls. Eur J Clin Nutr. 1992 Nov;46(11):823-31.

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113. Schneede J, Ueland PM. Novel and established markers of cobalamin deficiency: complementary or exclusive diagnostic strategies. Semin Vasc Med. 2005 May;5(2):140-55

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117. Srikumar TS, Johansson GK, Ockerman PA, Gustafsson JA, Akesson B. Trace element status in healthy subjects switching from a mixed to a lactovegetarian diet for 12 mo. Am J Clin Nutr. 1992 Apr;55(4):885-90.

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120. Szymanski KM, Wheeler DC, Mucci LA. Fish consumption and prostate cancer risk: a review and meta-analysis. Am J Clin Nutr. 2010 Nov;92(5):1223-33.

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Is human fecundity declining in Western countries? Hum Reprod. 2010 Jun;25(6):1348-53.

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131. Waldmann A, Dörr B, Koschizke JW, Leitzmann C, Hahn A. Dietary intake of vitamin B6 and concentration of vitamin B6 in blood samples of German vegans. Public Health Nutr. 2006 Sep;9(6):779-84.

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Selecting Seafood for Health and Sustainability | The Paleo Diet

There’s no question that seafood is a great source of protein and omega-3 fatty acids, and that it should form an integral part of the Paleo Diet. But seafood doesn’t thrive in polluted waters, overfished waters, or in habitats damaged by fishing gear. So to get the good without the bad—and to ensure we have it for years to come—we need to know which species have the holy trinity of seafood: sustainable, safe, and nutritious.

Sustainable

Sustainably caught fish may seem like a nice-to-have, but it should really be on par with nutrition for importance when selecting seafood. Not only do we want our food to be harvested or caught in its highest nutritive state, we want that to continue indefinitely. It hasn’t always been that way, but more and more fisheries are making sustainability a reality by considering the health of ecosystems and fish populations as well as their profits. Seafood Watch® makes science-based recommendationsfor sustainable seafood.1,2,3 Here’s their current list of best choices, good alternatives, and choices to avoid.

Selecting Seafood for Health and Sustainability

The seafood recommendations in this guide are credited to the Monterey Bay Aquarium Foundation ©2014. All rights reserved.

Download the PDF

Safe

In the seafood world, mercury, dioxins, and PCBs are the usual suspects when it comes to contamination. They’re not normally features of a “healthy and abundant stock” which is a fundamental criterion for sustainability1—so if you’re choosing sustainable, you’re likely choosing safe too. In addition, SeafoodWatch® posts health alerts if there are specific concerns for human health from a fishery.

Mercury, however, is a changing story. Mercury accumulates in fat tissues of large, long-lived predatory fish or shellfish, ultimately ending up on our dinner plates. We’ve been cautioned to limit these species in our diets, but surprisingly, that’s not the whole story. Mercury readily and irreversibly binds to selenium,4 which means that as long as the fish you’re eating has more selenium than mercury, your body won’t actually be retaining the mercury you ingest. And since the oceans are full of selenium, most ocean fish are perfectly safe to eat.5,6 Simply avoid shark and limit swordfish, tilefish, and king mackerel or use this infographic to moderate your consumption . Also keep in mind that in freshwater, mercury and selenium levels vary greatly with the composition of the surrounding soil. Check with your local authorities for health alerts.

Nutritious

Fish are great sources of vitamins and minerals as well as protein, but the biggest benefit from eating fish is the omega-3 fatty acids EPA and DHA.7 Anyone who’s had king salmon and a haddock fillet can tell you, however, that all fish are not created equal when it comes to fat—and they’re not all created equal when it comes to omega-3 to omega-6 ratios either—and that matters! Here’s some nutritional data from the USDA for some popular fish and shellfish.6

Sustainable Choices in SeafoodSustainable Choices in Seafood

Highlighted numbers in the first four columns are amounts greater than 1 g/100 g; highlighted numbers in the last column are the fish with ratios greater than 5. A few things jump out.

  • Total fat isn’t everything: the number of fish hitting 1 g/100 g decreases as we move from total fat to polyunsaturated fat to omega-3s.
  • Atlantic mackerel, chinook salmon, herring, swordfish, and Bluefin tuna have high total fat and great omega-3/omega-6 ratios.
  • Only farmed Atlantic salmon has more than 1 g/100 g of omega-6s.
  • All but tilapia have an omega-3/omega-6 ratio greater than 1.
  • There doesn’t seem to be a relationship between total fat and the omega-3/omega-6 ratio. There are high fat options with low ratios (Atlantic salmon) and high ratio options with lower fat (squid).

Sustainable + Safe + Nutritious

So can we have our fish and eat it too? Yes! There is an impressively wide array of sustainable options to choose from, and we can assume that they’re safe choices, not only because they’re sustainable, but because they’re high in selenium. Many of those sustainable options are also fatty fish with great omega-3/omega-6 ratios (anything above 1 is great). SeafoodWatch® compiled their “Super Green List” based on these criteria, but let’s look at the poor performers to compare.

  • Atlantic salmon: not sustainably caught, high omega-6s, ratio close to 1
  • Bluefin tuna: great fat profile, great ratio, but not sustainable
  • Tilapia: sustainably farmed, but lower in fat, ratio less than 1
  • Sharks: more mercury than selenium, not sustainably caught

The bottom line: while some seafood looks good in the nutritional breakdown, from a sustainability standpoint, some species may be better than others. So, eat your recommended portion of omega-3s, but choose options that tick all the boxes for your health as well as the ocean’s.

Andrea MooreAndrea Moore has dipped her toes in a lot of ponds, lakes, and oceans over the years. She has adventured around the world doing odd jobs and studying biology, languages, and sailing.

Now surprisingly settled in Halifax, Nova Scotia, Andrea’s still up to a bit of everything as a marine biologist, a writer, and an editor, living the Paleo lifestyle.

fix-logoFix.com is a lifestyle blog devoted to bringing you expert content to make your life easier. From products, to food, to fishing, to projects, we’ll be providing you with a daily fix of content from our experienced and knowledgeable team of writers.

 

REFERENCES

1. Monterey Bay Aquarium. Developing Seafood Watch® Recommendations. Version: January 23, 2014.

2. Monterey Bay Aquarium. Seafood Watch® Criteria for Aquaculture. Accessed: September 5, 2014.

3. Monterey Bay Aquarium. Seafood Watch ® Criteria for Fisheries. Version: March 31, 2014.

4. Ralston NVC, Ralston CR, Blackwell 3rd JL, Raymond LJ. Dietary and tissue selenium in relation to methylmercury toxicity. NeuroToxicology 2008;29(5):802-11.

5. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, December 2010.

6. US Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory. USDA National Nutrient Database for Standard Reference, Release 27. Version Current: August 2014.

7. Kidd PM. Omega-3 DHA and EPA for cognition, behavior, and mood: clinical findings and structural-functional synergies with cell membrane phospholipids. Altern Med Rev 2007;12(3):207-27.

Metabolic Syndrome and the Brain

Metabolic syndrome is an increasingly prevalent problem, not only in developed countries, but in developing countries as well.1, 2 The cluster of risk factors, which comprise metabolic syndrome, are usually thought to be strictly related to obesity.3 However, research shows that metabolic syndrome is correlated with severe cognitive dysfunction as well.4, 5 Risk factors for metabolic syndrome are defined as: raised blood pressure, dyslipidemia (raised triglycerides and lowered high-density lipoprotein cholesterol), raised fasting glucose, and central obesity.6, 7
Definition of Metabolic Syndrome

So what exactly causes metabolic syndrome? Scientific literature suggests Westernization of diet is part of the problem.8 When we look at the brain impairment associated with metabolic syndrome, there are a variety of proposed causative mechanisms including impaired vascular reactivity, neuroinflammation, oxidative stress, and abnormal brain lipid metabolism.9

Hypothesized Brain Vascuar Reactivity

Model describing hypothesized brain vascular reactivity abnormalities resulting in brain impairments.

Interestingly, at least one study has shown that men are more affected, cognitively, than women.10 A comprehensive study on metabolic syndrome and the brain, found rats fed an omega-3 deficient diet exhibited memory deficits, which were further exacerbated by fructose intake.11 This demonstrates that systemic inflammation and high sugar intake, specifically fructose, may be two possible precursors to cognitive decline, as well as obesity. It is also important to note the prevalence of a hypercaloric diet consisting of a high sugar intake and highly processed foods has coincided with an exponential rise in diabetes and metabolic syndrome, as well as cardiovascular diseases and cancer.12 Nutrient intake directly correlates with brain volume as shown in the Nutrient Biomarker Pattern Score Diagram.13

Metabolic Syndrome Nutrient Biomarker

Nutrient biomarker patterns and volumetric MRI (n = 42) Total cerebral brain volume (A, B) expressed as a % of total intracranial volume; white matter hyperintensity volume (C) includes periventricular and subcortical deep signals expressed as a % of total cerebral brain volume; x-axis represents the standardized score for NBP1-BCDE, NBP8–trans fat, and NBP5-marine ω-3 patterns.

Metabolic syndrome and cognitive dysfunction can further be explained via a 2011 study, which specifically showed how omega-3 deficiencies during pregnancy could affect multiple cognitive factors of new born offspring.14 Omega-3 deficiency was also shown to have effects on levels of brain-derived neurotrophic factor, an important gene in regulating stress, and in the biology of mood disorders.15 The image below shows how inadequate omega-3 intake can lead to cognitive and mood dysfunction.

Metabolic Syndrome Diagram 4

Schematic representation for potential pathways by which n-3 dietary deficiency may enhance vulnerability to cognitive and mood disorders.

Omega-3 fatty acid deficiency, specifically an inadequate dietary intake of docosahexaenoic acid (DHA), is a recurring problem across these studies. DHA is vital to brain development, mood, and many other important physiological and cognitive functions.16 Other studies have shown brain tissue decline even early in the metabolic syndrome.17 High fructose consumption with an omega-3 deficient diet disrupts membrane homeostasis.18 Metabolic syndrome and brain dysfunction is even seen in adolescents, despite their much shorter lifespan.19 Researchers stated adolescents with metabolic syndrome show significantly lower arithmetic, spelling, attention, and mental flexibility and a trend for lower overall intelligence.

The takeaway: Westernization of diets, specifically over consumption of fructose, is closely linked with developing metabolic syndrome and its accompanying cognitive impairment. Deficiencies in anti-inflammatory omega-3 fatty acids have also been shown to correlate with metabolic syndrome and cognitive decline. A simple path to a healthier life is to adopt a Paleo Diet, which is generally extremely low in fructose, and high in omega-3 fatty acids. By giving your brain (and body) the right nutrients, you can thrive in all areas of life.

References

1. Mozumdar A, Liguori G. Persistent increase of prevalence of metabolic syndrome among U.S. adults: NHANES III to NHANES 1999-2006. Diabetes Care. 2011;34(1):216-9.

2. Misra A, Bhardwaj S. Obesity and the metabolic syndrome in developing countries: focus on South Asians. Nestle Nutr Inst Workshop Ser. 2014;78:133-40.

3. Després JP, Lemieux I. Abdominal obesity and metabolic syndrome. Nature. 2006;444(7121):881-7.

4. Yaffe K, Weston AL, Blackwell T, Krueger KA. The metabolic syndrome and development of cognitive impairment among older women. Arch Neurol. 2009;66(3):324-8.

5. Taylor VH, Macqueen GM. Cognitive dysfunction associated with metabolic syndrome. Obes Rev. 2007;8(5):409-18.

6. Alberti KG, Eckel RH, Grundy SM, et al. Harmonizing the metabolic syndrome: a joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity. Circulation. 2009;120(16):1640-5.

7. Huang PL. A comprehensive definition for metabolic syndrome. Dis Model Mech. 2009;2(5-6):231-7.

8. Keller KB, Lemberg L. Obesity and the metabolic syndrome. Am J Crit Care. 2003;12(2):167-70.

9. Yates KF, Sweat V, Yau PL, Turchiano MM, Convit A. Impact of metabolic syndrome on cognition and brain: a selected review of the literature. Arterioscler Thromb Vasc Biol. 2012;32(9):2060-7.

10. Cavalieri M, Ropele S, Petrovic K, et al. Metabolic syndrome, brain magnetic resonance imaging, and cognition. Diabetes Care. 2010;33(12):2489-95.

11. Agrawal R, Gomez-pinilla F. ‘Metabolic syndrome’ in the brain: deficiency in omega-3 fatty acid exacerbates dysfunctions in insulin receptor signalling and cognition. J Physiol (Lond). 2012;590(Pt 10):2485-99.

12. Barnes JN, Joyner MJ. Sugar highs and lows: the impact of diet on cognitive function. J Physiol (Lond). 2012;590(Pt 12):2831.

13. Bowman GL, Silbert LC, Howieson D, et al. Nutrient biomarker patterns, cognitive function, and MRI measures of brain aging. Neurology. 2012;78(4):241-9.

14. Bhatia HS, Agrawal R, Sharma S, Huo YX, Ying Z, Gomez-pinilla F. Omega-3 fatty acid deficiency during brain maturation reduces neuronal and behavioral plasticity in adulthood. PLoS ONE. 2011;6(12):e28451.

15. Available at: //www.ncbi.nlm.nih.gov/gene/627. Accessed July 8, 2014.

16. Horrocks LA, Yeo YK. Health benefits of docosahexaenoic acid (DHA). Pharmacol Res. 1999;40(3):211-25.

17. Sala M, De roos A, Van den berg A, et al. Microstructural brain tissue damage in metabolic syndrome. Diabetes Care. 2014;37(2):493-500.

18. Agrawal R, Gomez-pinilla F. ‘Metabolic syndrome’ in the brain: deficiency in omega-3 fatty acid exacerbates dysfunctions in insulin receptor signalling and cognition. J Physiol (Lond). 2012;590(Pt 10):2485-99.

19. Yau PL, Castro MG, Tagani A, Tsui WH, Convit A. Obesity and metabolic syndrome and functional and structural brain impairments in adolescence. Pediatrics. 2012;130(4):e856-64.

Omega-3 vs. Omega-6: Rethinking the Hypothesis

When you’re eating a meal, you’re probably not thinking about macronutrients, like carbohydrates, fats and proteins. The vast majority of individuals following a Western diet aren’t consciously thinking is this food essential to the human body? It is important to note, however, that while there is no such thing as an “essential carbohydrate,”1 there are “essential fats.”2 Essential in the sense that the human body cannot make these fats endogenously,3 and therefore, must be obtained via diet or supplementation.4 Within the class of essential fats, we have omega-3, which has different forms such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (E’PA).5 However, omega-3 is more commonly known to the general populace as “fish oil.”

Omega 3 fatty acids are long chain in structure and found in a variety of foods.6 The action of these long chain fatty acids is commonly called “anti-inflammatory,” though this is a misnomer.7 They are simply less inflammatory than omega-6 fatty acids. Omega-3 FAs and omega-6 FAs compete for the same enzyme to eventually be converted into anti-inflammatory prostaglandins (PGE3) and less inflammatory leukotrienes and into pro-inflammatory prostaglandins (PGE2) and more inflammatory leukotrienes, respectively.8 This paper then goes on to declare, it is the ratio of omega-6 to omega-3 that is vital to reduce or promote the overall inflammatory state of the body.9,10,11 When we look to the habits of hunter-gatherers, the ratio of omega-6 to omega-3 has been estimated at 2:1 or 3:1.12 This is in contrast to the modern diet, which has been estimated at 10:1, or even 25:1.13

With this evidence, it is assumed that emulating the ratio of hunter-gatherers is correct, if we want to improve bio-markers of health.14 Certainly the theory that an inflammatory diet, full of omega-6 rich vegetable oils and very little omega-3 would likely lead to health problems, makes basic sense.15 However, newer research suggests both omega-6 and omega-3 FAs reduce the risk of heart disease, and the ratio of these fatty acids is “not useful and can be misleading.”16 One study reported that omega-6 FAs do not inhibit the beneficial effects of omega-3 FAs, and the combination of both fatty acids leads to the greatest reduction in levels of inflammation.17

However, the real issue here is that omega-3 FAs bind to G coupled-protein receptors, and cause broad anti-inflammatory effects.18 If you remove the omega-3 FAs from your diet, inflammation returns. This means that adequate omega-3 intake alone, regardless of omega-6 intake, is enough to stop inflammation in the body. The same is apparent when you look at the biochemical pathway of omega-6 and omega-3 FAs. They compete for the same enzyme19 through a process known as competitive inhibition.20

The best method of action to pursue, is to simply follow a Paleo Diet and eat plenty of fish rich in omega-3. If you want to avoid dietary intake of omega-3, and obtain the requirements solely from a supplement, DHA is preferable to all other forms of omega-3, since it can be retro converted into EPA.21 Only in the context of a very inflammatory diet (like the standard Western diet) does the ratio of omega-3 to 6 matter. Another case where the ratio would be of utmost importance, is if you aren’t getting any omega-3 FAs at all. This isn’t to say that the omega-3 to omega-6 ratio is completely irrelevant, but if you’re consuming a Paleo Diet, you will likely be getting the right amounts of these essential fatty acids for optimal health.

References

1. Westman EC. Is dietary carbohydrate essential for human nutrition?. Am J Clin Nutr. 2002;75(5):951-3.

2. Insel, Paul. Nutrition: Custom Edition. 4th Edition. Jones & Bartlett Learning, 2010; 182.

3. Chang CY, Ke DS, Chen JY. Essential fatty acids and human brain. Acta Neurol Taiwan. 2009;18(4):231-41.

4. Singh M. Essential fatty acids, DHA and human brain. Indian J Pediatr. 2005;72(3):239-42.

5. Wainwright PE. Dietary essential fatty acids and brain function: a developmental perspective on mechanisms. Proc Nutr Soc. 2002;61(1):61-9.

6. Meyer BJ, Mann NJ, Lewis JL, Milligan GC, Sinclair AJ, Howe PR. Dietary intakes and food sources of omega-6 and omega-3 polyunsaturated fatty acids. Lipids. 2003;38(4):391-8.

7. Foitzik T, Eibl G, Schneider P, Wenger FA, Jacobi CA, Buhr HJ. Omega-3 fatty acid supplementation increases anti-inflammatory cytokines and attenuates systemic disease sequelae in experimental pancreatitis. JPEN J Parenter Enteral Nutr. 2002;26(6):351-6.

8. Macsai MS. The role of omega-3 dietary supplementation in blepharitis and meibomian gland dysfunction (an AOS thesis). Trans Am Ophthalmol Soc. 2008;106:336-56.

9. Simopoulos AP. The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomed Pharmacother. 2002;56(8):365-79.

10. Gómez candela C, Bermejo lópez LM, Loria kohen V. Importance of a balanced omega 6/omega 3 ratio for the maintenance of health: nutritional recommendations. Nutr Hosp. 2011;26(2):323-9.

11. Simopoulos AP. The omega-6/omega-3 fatty acid ratio, genetic variation, and cardiovascular disease. Asia Pac J Clin Nutr. 2008;17 Suppl 1:131-4.

12. Cordain L, Eaton SB, Sebastian A, et al. Origins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr. 2005;81(2):341-54.

13. Yan L, Bai XL, Fang ZF, Che LQ, Xu SY, Wu D. Effect of different dietary omega-3/omega-6 fatty acid ratios on reproduction in male rats. Lipids Health Dis. 2013;12:33.

14. Apte SA, Cavazos DA, Whelan KA, Degraffenried LA. A low dietary ratio of omega-6 to omega-3 Fatty acids may delay progression of prostate cancer. Nutr Cancer. 2013;65(4):556-62.

15. Kang JX, Liu A. The role of the tissue omega-6/omega-3 fatty acid ratio in regulating tumor angiogenesis. Cancer Metastasis Rev. 2013;32(1-2):201-10.

16. Anton SD, Heekin K, Simkins C, Acosta A. Differential effects of adulterated versus unadulterated forms of linoleic acid on cardiovascular health. J Integr Med. 2013;11(1):2-10.

17. Pischon T, Hankinson SE, Hotamisligil GS, Rifai N, Willett WC, Rimm EB. Habitual dietary intake of n-3 and n-6 fatty acids in relation to inflammatory markers among US men and women. Circulation. 2003; 108(2): 155-160.

18. Oh DY, Talukdar S, Bae EJ, et al. GPR120 is an omega-3 fatty acid receptor mediating potent anti-inflammatory and insulin-sensitizing effects. Cell. 2010;142(5):687-98.

19. Babcock TA, Novak T, Ong E, Jho DH, Helton WS, Espat NJ. Modulation of lipopolysaccharide-stimulated macrophage tumor necrosis factor-alpha production by omega-3 fatty acid is associated with differential cyclooxygenase-2 protein expression and is independent of interleukin-10. J Surg Res. 2002;107(1):135-9.

20. Oleñik A, Mahillo-fernández I, Alejandre-alba N, et al. Benefits of omega-3 fatty acid dietary supplementation on health-related quality of life in patients with meibomian gland dysfunction. Clin Ophthalmol. 2014;8:831-6.

21. Conquer JA, Holub BJ. Dietary docosahexaenoic acid as a source of eicosapentaenoic acid in vegetarians and omnivores. Lipids. 1997;32(3):341-5.

Spicy Salmon | The Paleo Diet

Spicy salmon with avocado and yams balances your omega-3 intake with healthful fats. Nothing beats a little heat to ring in the sizzling summer season.

Ingredients

Serves 1-2

  • 1/3 Salmon fillet, skinned
  • Basil, Thyme, Rosemary, Oregano, Sage, chopped
  • Black Pepper, Red Pepper Flakes
  • 3-4 Garlic cloves, peeled and chopped
  • ½ Medium onion, diced
  • 1 Jalapeno pepper, chopped
  • Coconut or Extra Virgin Olive Oil
  • 1 Avocado
  • 1 Medium yam or sweet potato
  • Green chile sauce or salsa Optional

Directions

1. Dice yam into .5 x .5 inch sections.

2. Heat 1 tbsp coconut or olive oil in a Cast Iron pan on Low.

3. Stir in diced yams, and brown edges, ensuring they do not burn. Yams tend to cook slower than the salmon, so if you timed this recipe correctly, both the salmon and yams should finish cooking at the same time.

4. In a second Teflan pan, combine garlic, jalapenos and onions with 1 tbsp of coconut or olive oil.

5. Add salmon fillet and sprinkle chopped basil, thyme, oregano, rosemary, sage, and black and red pepper over the salmon fillet, to taste.

6. Break up salmon with a spatula and distribute spices and ingredients evenly.

7. Cook salmon until flaky.

8. Garnish with diced avocado and a generous serving of Paleo-approved green chili sauce or salsa.

9. Side Note: Freshly brewed green tea complements this meal very well!

10. Bon appétit!

The Paleo Diet Recipe Library

Nuts | The Paleo Diet

Do you find yourself having difficulty shedding weight on your Paleo regime? Or perhaps you’re still experiencing GI distress or frequent breakouts even though you’ve cut out the gluten, the dairy and the legumes.

Too many nuts, or the wrong type of nuts could be causing the problem.

Nuts can indeed be a part of the Paleo Diet when eaten in moderation: “in moderation” being the key takeaway message.

Since nuts are high in inflammatory Omega-6 and low in anti-inflammatory Omega-3, they should be regarding more as a garnish than a regular, go-to source of dietary fat.

The fats we should rely on regularly are raw avocados, coconut oil and extra virgin olive oil, as well as the fats we find with our protein sources, like wild salmon or the occasional fattier cut of grass fed meat, like a nice rib-eye.

Are All Nuts Created Equal?

Not at all.

We must factor in not only the type of nut, but also how the nut might be processed.

  • Raw, sprouted nuts are best, whereas you should steer clear of those found in large canisters, roasted in peanut oil. By soaking nuts and allowing them to sprout, we can reduce the amount of phytates we consume when we eat a handful of them with an apple as a snack, for example.
  • Surprisingly, almonds, which we see in abundance in many forms and varieties, have one of the worst Omega 3:6 ratios, with virtually no detectable Omega-3s!
  • Walnuts, Macadamias and Brazil Nuts, however, rank as the top three in their ratio which is more favorable, but still not ideal.

Don’t make the common mistake of buying a huge vat of nuts and bringing them to the office to “snack on” throughout the day. Far too often this ends in too many calories, an unbalanced macronutrient profile and an upset stomach.

How many nuts are too many nuts?

Simply put, if you’re eating any nuts more often than as the occasional garnish, it may be too much. Because they’re easy to purchase, easy to eat and require zero preparation, many people make the mistake of making them their go-to snack for the office or home, and end up consuming hundreds of extra calories each day without even realizing it.

But why are some nuts ok, but not some grains or some legumes?

It comes down to portion sizes and frequency. We’re only meant to be eating a small portion, as a garnish, on occasion, whereas with pasta, bread or bagels, the amount eaten in the typical Standard American Diet is closer to cupfuls.

A good example of how many nuts to eat might include a tablespoon of raw walnuts on a salad or a handful of raw almonds with an apple, some sliced turkey and spinach made into a wrap a couple times per week is the way to go.

Eating a vat of salted nuts, roasted in peanut oil that you purchased on sale at Costco each week is the wrong approach.

Are Nuts for Everyone?

Certain populations may need to be even more careful with nuts, such as those with autoimmune conditions. While some can tolerate nuts and seeds others cannot. The best approach is to go nut-free for a month on top of the standard Paleo Diet and then test to see if you react.

Storing

Because of their high fat content, nuts kept in the freezer can be eaten in that state. They won’t freeze into a rock-solid piece of ice the way a piece of lean chicken or veggies would.

Rather than following the budget friendly strategy of buying in bulk, only to find that two pound bag of organic raw walnuts still sitting in your cupboard two months later and not tasting so great, keeping them in the freezer proves to be cost-effective too, as nothing will spoil and go to waste.

For an easy to make treat, rinse, then freeze some organic grapes or a sliced banana. Paired with a handful of macadamias and topped with a dash of cinnamon and ginger, this makes an incredibly decadent “something sweet” way to finish a meal, far more representative of True Paleo than any treat.

Zero processing and loads of flavor is the way to go.

For a special occasion, create the decadent Raw Chocolate Covered Walnuts with Berries.

There has been extensive debate within the Paleo community recently surrounding the validity of certain cooking oils while following The Paleo Diet.

Hunter-gatherers would have not had access to most cooking oils available to modern society. That being said, animal fats were likely consumed and used as a substitute for cooking oils that are commonly consumed today. Grilling eliminates the need for cooking with oil in pans, but grilling food for every meal is not very realistic for the average individual following a contemporary Paleo Diet.

However, there are a number of common cooking oils that should never be consumed while following The Paleo Diet. These include:

  • Soybean Oil: Often partially hydrogenated and is highly inflammatory due to the disproportionately high ratio of omega-6 to omega-3 fatty acids.
  • Canola Oil: Derived from the unpalatable rapeseed plant, the oil is stripped of erucic acid to make it edible. Canola oil is often praised for its omega-3 content, but health practitioners often fail to account for the quick degradation of omega-3 fatty acids within the oil due to the 500 degree temperature that is required to manufacture the oil.
  • Cottonseed Oil: Derived from an inedible plant that is used in the textile industry, the oil is used in numerous processed foods including margarine, ice cream, bread, and packaged oysters. As with Canola, Cottonseed also has an unhealthy fatty acid profile and should be avoided at all costs.

Other cooking oils to avoid for rancidity, inflammatory properties, and an unbalanced fatty acid profile:

  • Safflower Oil
  • Sunflower Seed Oil
  • Sesame Seed Oil
  • Peanut Oil
  • Corn Oil
  • Vegetable OilGrape Seed Oil
Despite the overwhelming majority of unhealthy oils that are available for purchase at your average grocery store, there is still hope! Swap out the bad for the oils permitted when following The Paleo Diet.

  • Olive Oil: Fantastic for sauteing and as a salad dressing. It is fairly resistant to high heat, which makes it less prone to rancidity. It primarily consists of monounsaturated fats, which are considered safe and healthy.
  • Coconut Oil: While the tropical, shelf-stable oil is relatively high in saturated fats, the saturated fat content should not be a concern and allows for the oil to remain stable at high temperatures. Coconut oil is also very rich in a medium chain fatty acid known as Lauric Acid, which is recognized for its antimicrobial and antifungal properties.
  • Animal Fat: Realistically, this is the closest to a hunter-gatherer cooking fat or oil. Grass-fed beef tallow is preferred. Duck fat is also allowed. However, be careful when consuming fat from pork or chicken, as both contain significantly higher quantities of polyunsaturated fats.

Although there are numerous toxic and potentially lethal species of mushroom species, you should not be worried about consuming the mushrooms you find at your choice grocer. In all likelihood, our hunter-gatherer ancestors likely indulged in various types of mushrooms on a semi-regular basis, knowing the distinct properties to exclude poisonous species. Mushrooms are also relatively low on the glycemic index and are rich in selenium, potassium, riboflavin, niacin – all optimal for your health. Let the mushroom hunting adventures ensue!

Kyle Cordain
The Paleo Diet Team

Mushroom Sauté

Cooking Oils | The Paleo Diet

3 – 4 Servings

Ingredients

  • 2 cups fresh mushrooms, sliced thin
  • ½ sweet onion, sliced thin
  • 2 fresh garlic cloves, pressed
  • 2 tbsp extra virgin olive oil
  • ¼ cup red wine
  • 2 leaves fresh basil finely chopped
  • 1 sprig fresh rosemary, minced, stem removed
  • Grass-Fed Beef or Buffalo Steaks

Directions

1. In large fry pan, saute onions and garlic in olive oil over medium heat until onions are tender.

2. Stir in mushrooms and remaining ingredients.

3. Reduce heat to low and simmer for 5 minutes.

4. Serve over fresh grass-fed beef or buffalo steaks.

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